我使用ExchangeUserCredentialForToken函数从授权服务器获取令牌。当我的用户存在于我的数据库中时，它的工作正常，但当凭据不正确时，我想向客户端发回一条消息。我使用以下2行代码来设置错误消息：
context.SetError("Autorization Error","The username or password is incorrect!");
context.Rejected();
但是在客户端，我只得到协议错误(错误400)。你可以帮助我如何在授权服务器上得到服务器端的错误信息？
授权服务器的完整应用配置：
using Constants;
using Microsoft.Owin;
using Microsoft.Owin.Security;
using Microsoft.Owin.Security.Cookies;
using Microsoft.Owin.Security.Infrastructure;
using Microsoft.Owin.Security.OAuth;
using Owin;
using System;
using System.Collections.Concurrent;
using System.Linq;
using System.Security.Claims;
using System.Security.Principal;
using System.Threading.Tasks;
using AuthorizationServer.Entities;
using AuthorizationServer.Entities.Infrastructure.Abstract;
using AuthorizationServer.Entities.Infrastructure.Concrete;
namespace AuthorizationServer
{
public partial class Startup
{
private IEmployeeRepository Repository;
public void ConfigureAuth(IAppBuilder app)
{
//instanciate the repository
Repository = new EmployeeRepository();
// Enable Application Sign In Cookie
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = "Application",AuthenticationMode = AuthenticationMode.Passive,LoginPath = new PathString(Paths.LoginPath),logoutPath = new PathString(Paths.logoutPath),});
// Enable External Sign In Cookie
app.SetDefaultSignInAsAuthenticationType("External");
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = "External",CookieName = CookieAuthenticationDefaults.CookiePrefix + "External",ExpireTimeSpan = TimeSpan.FromMinutes(5),});
// Enable google authentication
app.UseGoogleAuthentication();
// Setup Authorization Server
app.USEOAuthAuthorizationServer(new OAuthAuthorizationServerOptions
{
AuthorizeEndpointPath = new PathString(Paths.AuthorizePath),TokenEndpointPath = new PathString(Paths.TokenPath),ApplicationCanDisplayErrors = true,#if DEBUG
AllowInsecureHttp = true,#endif
// Authorization server provider which controls the lifecycle of Authorization Server
Provider = new OAuthAuthorizationServerProvider
{
OnValidateClientRedirectUri = ValidateClientRedirectUri,OnValidateClientAuthentication = ValidateClientAuthentication,OnGrantResourceOwnerCredentials = GrantResourceOwnerCredentials,OnGrantClientCredentials = GrantClientCredetails
},// Authorization code provider which creates and receives authorization code
AuthorizationCodeProvider = new AuthenticationTokenProvider
{
OnCreate = CreateAuthenticationCode,OnReceive = ReceiveAuthenticationCode,},// Refresh token provider which creates and receives referesh token
RefreshTokenProvider = new AuthenticationTokenProvider
{
OnCreate = CreateRefreshToken,OnReceive = ReceiveRefreshToken,}
});
// indicate our intent to use bearer authentication
app.USEOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions
{
AuthenticationType = "Bearer",AuthenticationMode = Microsoft.Owin.Security.AuthenticationMode.Active
});
}
private Task ValidateClientRedirectUri(OAuthValidateClientRedirectUriContext context)
{
if (context.ClientId == Clients.Client1.Id)
{
context.Validated(Clients.Client1.RedirectUrl);
}
else if (context.ClientId == Clients.Client2.Id)
{
context.Validated(Clients.Client2.RedirectUrl);
}
return Task.FromResult(0);
}
private Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
{
string clientname;
string clientpassword;
if (context.TryGetBasicCredentials(out clientname,out clientpassword) ||
context.TryGetFormCredentials(out clientname,out clientpassword))
{
employee Employee = Repository.GetEmployee(clientname,clientpassword);
if (Employee != null)
{
context.Validated();
}
else
{
context.SetError("Autorization Error","The username or password is incorrect!");
context.Rejected();
}
}
return Task.FromResult(0);
}
private Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
{
var identity = new ClaimsIdentity(new GenericIdentity(context.UserName,OAuthDefaults.AuthenticationType),context.Scope.Select(x => new Claim("urn:oauth:scope",x)));
context.Validated(identity);
return Task.FromResult(0);
}
private Task GrantClientCredetails(OAuthGrantClientCredentialsContext context)
{
var identity = new ClaimsIdentity(new GenericIdentity(context.ClientId,x)));
context.Validated(identity);
return Task.FromResult(0);
}
private readonly ConcurrentDictionary<string,string> _authenticationCodes =
new ConcurrentDictionary<string,string>(StringComparer.Ordinal);
private void CreateAuthenticationCode(AuthenticationTokenCreateContext context)
{
context.SetToken(Guid.NewGuid().ToString("n") + Guid.NewGuid().ToString("n"));
_authenticationCodes[context.Token] = context.SerializeTicket();
}
private void ReceiveAuthenticationCode(AuthenticationTokenReceiveContext context)
{
string value;
if (_authenticationCodes.TryRemove(context.Token,out value))
{
context.DeserializeTicket(value);
}
}
private void CreateRefreshToken(AuthenticationTokenCreateContext context)
{
context.SetToken(context.SerializeTicket());
}
private void ReceiveRefreshToken(AuthenticationTokenReceiveContext context)
{
context.DeserializeTicket(context.Token);
}
}
}
解决方法
这是一个完整的解决方案，使用Jeff的概念与我的原始帖子相结合。
1)在上下文中设置错误消息
如果您在设置错误消息后调用context.Rejected()，则会删除错误消息(请参见下面的示例)：
context.SetError("Account locked","You have exceeded the total allowed Failed logins. Please try back in an hour.");
context.Rejected();
您将要从您的任务中删除context.Rejected()。请注意，被拒绝和SetError方法的定义是：
拒绝：
Marks this context as not validated by the application. IsValidated and HasError become false as a result of calling.
SETERROR：
Marks this context as not validated by the application and assigns varIoUs error information properties. HasError becomes true and IsValidated becomes false as a result of calling.
再次，通过在设置错误后调用Rejected方法，上下文将被标记为没有错误，错误消息将被删除。
2)设置响应的状态代码：使用Jeff的例子，用一点点旋转。
而不是使用魔术字符串，我将创建一个全局属性来设置状态代码的标签。在静态全局类中，创建一个用于标识状态代码的属性(我使用X-Challenge，但是当然可以使用任何您选择的内容)。这将用于标记响应中添加的标题属性。
public static class ServerGlobalVariables
{
//Your other properties...
public const string OwinChallengeFlag = "X-Challenge";
}
然后在您的OAuthAuthorizationServerProvider的各种任务中，您将添加标签作为响应中的新标头值的键。将HttpStatusCode枚举与全局标志结合使用，您将可以访问所有各种状态代码，并避免使用魔术字符串。
//Set the error message
context.SetError("Account locked","You have exceeded the total allowed Failed logins. Please try back in an hour.");
//Add your flag to the header of the response
context.Response.Headers.Add(ServerGlobalVariables.OwinChallengeFlag,new[] { ((int)HttpStatusCode.Unauthorized).ToString() });
在客户OwinMiddleware中，您可以使用全局变量搜索标题中的标志：
//This class handles all the OwinMiddleware responses,so the name should
//not just focus on invalid authentication
public class CustomAuthenticationMiddleware : OwinMiddleware
{
public CustomAuthenticationMiddleware(OwinMiddleware next)
: base(next)
{
}
public override async Task Invoke(IOwinContext context)
{
await Next.Invoke(context);
if (context.Response.StatusCode == 400
&& context.Response.Headers.ContainsKey(
ServerGlobalVariables.OwinChallengeFlag))
{
var headerValues = context.Response.Headers.GetValues
(ServerGlobalVariables.OwinChallengeFlag);
context.Response.StatusCode =
Convert.ToInt16(headerValues.FirstOrDefault());
context.Response.Headers.Remove(
ServerGlobalVariables.OwinChallengeFlag);
}
}
}
最后，正如Jeff指出的那样，您必须在Startup.Configuration或Startup.ConfigureAuth方法中注册此自定义OwinMiddleware：
app.Use<CustomAuthenticationMiddleware>();
使用上述解决方案，您现在可以设置状态代码和自定义错误消息，如下所示：
>无效的用户名或密码
>此帐户已超过最大尝试次数
>电子邮件帐户尚未确认
在客户端应用程序中，需要捕获并处理ProtocolException。这样的事情会给你答案：
//Need to create a class to deserialize the Json
//Create this somewhere in your application
public class OAuthErrorMsg
{
public string error { get; set; }
public string error_description { get; set; }
public string error_uri { get; set; }
}
//Need to make sure to include Newtonsoft.Json
using Newtonsoft.Json;
//Code for your object....
private void login()
{
try
{
var state = _webServerClient.ExchangeUserCredentialForToken(
this.emailTextBox.Text,this.passwordBox.Password.Trim(),scopes: new string[] { "PublicProfile" });
_accessToken = state.AccessToken;
_refreshToken = state.RefreshToken;
}
catch (ProtocolException ex)
{
var webException = ex.InnerException as WebException;
OAuthErrorMsg error =
JsonConvert.DeserializeObject<OAuthErrorMsg>(
ExtractResponseString(webException));
var errorMessage = error.error_description;
//Now it's up to you how you process the errorMessage
}
}
public static string ExtractResponseString(WebException webException)
{
if (webException == null || webException.Response == null)
return null;
var responseStream =
webException.Response.GetResponseStream() as MemoryStream;
if (responseStream == null)
return null;
var responseBytes = responseStream.ToArray();
var responseString = Encoding.UTF8.GetString(responseBytes);
return responseString;
}
我已经测试了这个，它在VS2013 Pro与4.5完美的工作！
(请注意，我没有包括所有必需的命名空间或附加代码，因为这将因应用程序而异：WPF，MVC或Winform。另外，我没有讨论错误处理，所以你需要确保在您的解决方案中实施适当的错误处理。)
